Could Jet Lag Make You Obese?
Here’s a fascinating new study, published last week in the journal Cell. When you get off a plane after a long flight, jet lag doesn’t just make you “feel” bad. It actually upsets the microbes in your gut. And those disoriented microbes make you more likely to develop obesity and glucose intolerance. Researchers have discovered a “transkingdom” effect of disturbed circadian rhythm, and it may turn out to be the reason that shift workers, over time, have a 40% higher rate of type-2 diabetes.
A group at the Weizmann Institute took mice and put them on a schedule that mimicked 8 hours of jet lag. As senior author Eran Elinav told Time magazine, “In the presence of jet lag, the microbes [in the intestines of the mice] were completely messed up.” The jet lagged mice themselves became obese and glucose intolerant. Next, the team took some of those messed up microbes and transferred them to germ-free mice. The new mice also became obese and glucose intolerant. Finally, the researchers transferred microbes from humans who were jet lagged into germ-free mice. The same thing happened-–more obesity and glucose intolerance. Given the recent evidence that we manage to give ourselves “jet lag” without even stepping on a plane, these findings are especially alarming.
It’s a remarkable study. It brings together two previously separate areas of medical research–our microbiome and our circadian rhythm. They turn out to be linked. The authors use a wonderfully weird phrase in the published study. “These findings provide evidence of coordinated metaorganism diurnal rhythmicity.” And their findings provide evidence of the importance of that coordinated metaorganism diurnal rhythmicity. Our lives are fantastically strange, and they are intertwined with the lives of other organisms in ways that continue to astonish us.